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Receptor‐like kinases (RLKs) represent the largest group of cell surface receptors in plants. The monophyletic leucine‐rich repeat (LRR)‐RLK subfamily II is considered to contain the somatic embryogenesis receptor kinases (SERKs) and NSP‐interacting kinases known to be involved in developmental processes and cellular immunity in plants. There are only a few published studies on the phylogenetics of LRR‐RLKII; unfortunately these suffer from poor taxon/gene sampling. Hence, it is not clear how many and what main clades this family contains, let alone what structure–function relationships exist. We used 1342 protein sequences annotated as ‘SERK’ and ‘SERK‐like’ plus related sequences in order to estimate phylogeny within the LRR‐RLKII clade, using the nematode protein kinase Pelle as an outgroup. We reconstruct five main clades (LRR‐RLKII 1–5), in each of which the main pattern of land plant relationships re‐occurs, confirming previous hypotheses that duplication events happened in this gene subfamily prior to divergence among land plant lineages. We show that domain structures and intron–exon boundaries within the five clades are well conserved in evolution. Furthermore, phylogenetic patterns based on the separate LRR and kinase parts of LRR‐RLKs are incongruent: whereas the LRR part supports a LRR‐RLKII 2/3 sister group relationship, the kinase part supports clades 1/2. We infer that the kinase part includes few ‘radical’ amino acid changes compared with the LRR part. Finally, our results confirm that amino acids involved in each LRR‐RLKII–receptor complex interaction are located at N‐capping residues, and that the short amino acid motifs of this interaction domain are highly conserved throughout evolution within the five LRR‐RLKII clades.  相似文献   
3.
Stelis, one of the largest genera within Pleurothallidinae, was recently recircumscribed to include a few hundred more species, most of which had previously been assigned to Pleurothallis. Here, a new phylogenetic analysis of Stelis and closely related genera based on DNA sequences from nuclear ITS and chloroplast matK, based on a much larger sample, is presented; it includes more than 100 species assigned to Stelis and covers all proposed groupings within the genus, many of which have not previously been represented. Clades are proposed to enable easier discussion of groups of closely related species; each clade is characterized morphologically, ecologically, and geographically to explain the evidence found in the molecular analysis. Discussion of the evolutionary trends of character states found in the genus in its broad sense is given. The current taxonomy of the group is given and the possible taxonomical implications of the findings presented here are discussed.  相似文献   
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Early diagnosis is important for effective disease management. Measurement of biomarkers present at the local level of the skin could be advantageous in facilitating the diagnostic process. The analysis of the proteome of suction blister fluid, representative for the interstitial fluid of the skin, is therefore a desirable first step in the search for potential biomarkers involved in biological pathways of particular diseases. Here, we describe a global analysis of the suction blister fluid proteome as potential body fluid for biomarker proteins. The suction blister fluid proteome was compared with a serum proteome analyzed using identical protocols. By using stringent criteria allowing less than 1% false positive identifications, we were able to detect, using identical experimental conditions and amount of starting material, 401 proteins in suction blister fluid and 240 proteins in serum. As a major result of our analysis we construct a prejudiced list of 34 proteins, relatively highly and uniquely detected in suction blister fluid as compared to serum, with established and putative characteristics as biomarkers. We conclude that suction blister fluid might potentially serve as a good alternative biomarker body fluid for diseases that involve the skin.  相似文献   
6.
The neural response to a stimulus is influenced by endogenous factors such as expectation and attention. Current research suggests that expectation and attention exert their effects in opposite directions, where expectation decreases neural activity in sensory areas, while attention increases it. However, expectation and attention are usually studied either in isolation or confounded with each other. A recent study suggests that expectation and attention may act jointly on sensory processing, by increasing the neural response to expected events when they are attended, but decreasing it when they are unattended. Here we test this hypothesis in an auditory temporal cueing paradigm using magnetoencephalography in humans. In our study participants attended to, or away from, tones that could arrive at expected or unexpected moments. We found a decrease in auditory beta band synchrony to expected (versus unexpected) tones if they were unattended, but no difference if they were attended. Modulations in beta power were already evident prior to the expected onset times of the tones. These findings suggest that expectation and attention jointly modulate sensory processing.  相似文献   
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Background  

The Red-headed krait (Bungarus flaviceps, Squamata: Serpentes: Elapidae) is a medically important venomous snake that inhabits South-East Asia. Although the venoms of most species of the snake genus Bungarus have been well characterized, a detailed compositional analysis of B. flaviceps is currently lacking.  相似文献   
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One of the key challenges of Li‐ion electrodes is enhancement of (dis)charge rates. This is severely hindered by the absence of a technique that allows direct and nondestructive observation of lithium ions in operating batteries. Direct observation of the Li‐ion concentration profiles using operando neutron depth profiling reveals that the rate‐limiting step is depended not only on the electrode morphology but also on the cycling rate itself. In the LiFePO4 electrodes phase nucleation limits the charge transport at the lowest cycling rates, whereas electronic conductivity is rate limiting at intermediate rates, and only at the highest rates ionic transport through the electrode is rate limiting. These novel insights into electrode kinetics are imperative for the improvement of Li‐ion batteries and show the large value of in situ NDP in Li‐ion battery research and development.  相似文献   
9.

Background

Influenza virus infections are responsible for significant morbidity worldwide and therefore it remains a high priority to develop more broadly protective vaccines. Adjuvation of current seasonal influenza vaccines has the potential to achieve this goal.

Methods

To assess the immune potentiating properties of Matrix-M?, mice were immunized with virosomal trivalent seasonal vaccine adjuvated with Matrix-M?. Serum samples were isolated to determine the hemagglutination inhibiting (HAI) antibody titers against vaccine homologous and heterologous strains. Furthermore, we assess whether adjuvation with Matrix-M? broadens the protective efficacy of the virosomal trivalent seasonal vaccine against vaccine homologous and heterologous influenza viruses.

Results

Matrix-M? adjuvation enhanced HAI antibody titers and protection against vaccine homologous strains. Interestingly, Matrix-M? adjuvation also resulted in HAI antibody titers against heterologous influenza B strains, but not against the tested influenza A strains. Even though the protection against heterologous influenza A was induced by the adjuvated vaccine, in the absence of HAI titers the protection was accompanied by severe clinical scores and body weight loss. In contrast, in the presence of heterologous HAI titers full protection against the heterologous influenza B strain without any disease symptoms was obtained.

Conclusion

The results of this study emphasize the promising potential of a Matrix-M?-adjuvated seasonal trivalent virosomal influenza vaccine. Adjuvation of trivalent virosomal vaccine does not only enhance homologous protection, but in addition induces protection against heterologous strains and thus provides overall more potent and broad protective immunity.
  相似文献   
10.
Worldwide, the incidence of obesity has increased dramatically over the past decades. More knowledge about the complex etiology of obesity is needed in order to find additional approaches for treatment and prevention. Investigating the exome sequencing data of 30 extremely obese subjects (BMI 45–65 kg/m2) shows that predicted damaging missense variants in olfactory receptor genes on chromosome 1q and rare predicted damaging variants in the protocadherin (PCDH) beta-cluster genes on chromosome 5q31, reported in our previous work, co-localize in subjects with extreme obesity. This implies a synergistic effect between genetic variation in these gene clusters in the predisposition to extreme obesity. Evidence for a general involvement of the olfactory transduction pathway on itself could not be found. Bioinformatic analysis indicates a specific involvement of the PCDH beta-cluster genes in controlling tissue development. Further mechanistic insight needs to await the identification of the ligands of the 1q olfactory receptors. Eventually, this may provide the possibility to manipulate food flavor in a way to reduce the risk of overeating and of extreme obesity in genetically predisposed subjects.

Electronic supplementary material

The online version of this article (doi:10.1007/s12263-015-0465-3) contains supplementary material, which is available to authorized users.  相似文献   
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